Blasting is used in the recovery of mineral resources, including in surface mining and quarrying for rock fragmentation and displacement of the broken rock. In blasting operations, detonators and explosives are buried in the ground, for example, in holes (e.g., bore holes) drilled into rock formations, etc., and the detonators are wired for external access to blasting machines that provide electrical signaling to initiate detonation of explosives. Electronic detonators have been developed which implement programmable delay times such that an array of detonators can be actuated in a controlled sequence. Electronic detonators are programmed using a logger, and later actuated or ignited using a blasting machine. The logger and the blasting machine to provide different voltages to a connected detonator in order to guard against inadvertent ignition during logging or programming operations. The electronic detonator typically includes a storage capacitor to store power to operate the internal detonator circuitry for reading and writing operations during programming by a logger. In addition, the detonator includes a firing capacitor that can be charged while the detonator is connected to a blasting machine, in order to selectively provide energy to an ignition element in response to a firing signal from the blasting machine. Ideally, the firing capacitor is not charged by a connected logger, but instead is charged only once a higher voltage blasting machine is connected to the detonator. In particular, each detonator in an electronic detonator blasting system may be queried electrically by a logger or programming unit, which contains voltage and current power sources. Such power sources should be insufficient to cause firing in the logger mode, or contain enough number of failure modes resulting in low likelihood of firing the electronic detonator during the logging or programming phase in the field. Optical means (e.g., bar code scanners, etc.) can instead be used for logging without any electrical signal exchange between the logger and electronic detonator, but it is more efficient to make electrical contact to also confirm that electrical communication exists and is reliable. Notably if there is a cut legwire, or a faulty electronic circuit inside the electronic detonator, such electrical contact, communication and/or diagnostics can alert the blaster of any potential issues, which would not otherwise be revealed using only optical logging. Further developments would therefore be beneficial to alleviate the probability of inadvertent firing during electrical communications to enhance the level of safety for electronic detonators connected to loggers over the boreholes containing explosives. The following documents are incorporated by reference in their entireties: U.S. Pat. Nos. 9,243,877; 5,309,841; 7,301,750; 4,393,779; European patents EP 1831636 and EP 2 352 964 and Published International Application WO 2011/014891.